Saylor Innovations Agent Bazaar by Saylor Innovations
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mirrored listing x402 eip155:8453

Determine whether an address on Base is a contract or an externally owned account

Determine whether an address on Base is a contract or an externally owned account. POST {"address":"0x..."} and receive isContract, the bytecode size in bytes and its keccak-256 hash. Useful before sending funds to an unfamiliar address.

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1000 (raw units)
price
1
calls / 30d
1
unique payers
2026-08-30
updated

Provider

x402-echo-service.onrender.com · discovered, not yet claimed by its owner

Payment (x402 accepts[])

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x9Cc774A8eD49d89cBA1A288F4a050B8F7FbA77EE",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000",
    "maxTimeoutSeconds": 300
  }
]

Output schema

{
  "bazaar": {
    "category": "Infra",
    "coverImage": "https://x402-echo-service.onrender.com/icon.png",
    "info": {
      "input": {
        "body": {
          "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
        },
        "bodyType": "json",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "example": {
          "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
          "codeSize": 1234,
          "isContract": true
        },
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "properties": {
            "body": {
              "additionalProperties": false,
              "properties": {
                "address": {
                  "type": "string"
                }
              },
              "required": [
                "address"
              ],
              "type": "object"
            },
            "bodyType": {
              "enum": [
                "json"
              ]
            },
            "method": {
              "enum": [
                "POST"
              ],
              "type": "string"
            },
            "type": {
              "const": "http"
            }
          },
          "required": [
            "type",
            "bodyType",
            "body",
            "method"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {
              "properties": {
                "address": {
                  "type": "string"
                },
                "codeSize": {
                  "type": "integer"
                },
                "isContract": {
                  "type": "boolean"
                }
              },
              "required": [
                "address",
                "isContract",
                "codeSize"
              ],
              "type": "object"
            },
            "type": {
              "const": "json"
            }
          },
          "required": [
            "type",
            "example"
          ],
          "type": "object"
        }
      },
      "required": [
        "input",
        "output"
      ],
      "type": "object"
    },
    "serviceName": "Contract Check",
    "summary": "Whether an address is a contract, with bytecode size.",
    "tags": [
      "contract",
      "bytecode",
      "base",
      "onchain",
      "eoa"
    ]
  }
}

Use it

curl

curl "https://x402-echo-service.onrender.com/chain/code"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://x402-echo-service.onrender.com/chain/code");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://x402-echo-service.onrender.com/chain/code")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Machine-readable

Everything on this page is also available as clean JSON at /resources/8180.json, and this resource appears in /discovery/resources and /discovery/search.